I bought a little notebook with a picture of Einstein on the front for notes/doodles/ideas. Not much of a journal, but it's perfect for jotting ideas and quotes and little tidbits of information down. The only problem is that I've been carrying it for about two weeks and I haven't cracked it open once. If you do buy one, just make sure to get into the habit of writing in it. Otherwise it's a waste of money. I need to do this too.
Curse you Rise Against! I was going to be the first comment! You and your fast rising posting!